Boston Bombings investigation

Credit: Getty Images

BOSTON, MA - APRIL 19: A swat team member scouts the perimeter of South Station on April 19, 2013 in Boston, Massachusetts. South Station was shut down and heavily guarded with police in response to the early morning shootings in Cambridge and Watertown, Massachusetts. After a car chase and shoot out with police, one suspect in the Boston Marathon bombing, Tamerlan Tsarnaev, 26, was shot and killed by police early morning April 19, and a manhunt is underway for his brother and second suspect, 19-year-old suspect Dzhokhar A. Tsarnaev. The two men, reportedly Chechen origin, are suspects in the bombings at the Boston Marathon on April 15, that killed three people and wounded at least 170. (Photo by Kayana Szymczak/Getty Images)